Definitions of yolk sac:
  • noun:   membranous structure enclosing the yolk of eggs in birds reptiles marsupials and some fishes; circulates nutrients to the developing embryo
  • noun:   membranous structure that functions as the circulatory system in mammal embryos until the heart becomes functional

Related words...

Search for yolk sac at other dictionaries: OneLook, Oxford, American Heritage, Merriam-Webster, Wikipedia

Help  Advanced  Feedback  Android  iPhone/iPad  API  Blog  Privacy

Copyright © 2020 Datamuse